1. Field of the Invention
The present invention relates to a retaining device, and more particularly, to a heat sink retaining device for attaching a heat sink on a chip unit.
2. Related Art
The booming development of the software and hardware pushes computers and the peripherals thereof to continuously improve in speed and quality. However, a following problem of the high chip temperature and the heat dissipation measures has become a non-ignorable problem or even a problem urgently calling for an effective solution. Therefore, in order to effectively reduce the operating temperature of the CPU or the chip on the motherboard of a computer, most of the designers dispose a group of heat sinks with preferred heat dissipation effect on the CPU or on the chip. The most common ones are, for example, a heat sink formed by aluminum extruded heat sink fins, or a heat sink comprising heat conducting piping, or a heat sink formed by aluminum extruded heat sink fins together with a fan.
When the above heat sinks are mounted and fixed, the parts such as an elastic clip, a regulating screw rod, or a set screw are commonly used to position the heat sink on surface of the CPU or the chip on the motherboard. However, as for the conventional positioning manner for locking the heat sink, holes must be formed on the surface of the chip for snapping a fastener, or other tools are required when locking with a screw, and spin-locking the screw will easily cause a damage of the heat sink fins. Moreover, the manner of snapping a fastener or an elastic member to a substrate not only has disadvantages concerning poor stability and being easy to be damaged, but also has defects concerning failure on improving the snapping effect as the elastic force is not a directly downward pressing snapping force, the non-uniform force and being difficult in disassembling. In order to solve the above problems, an adhering manner is provided in the conventional art to mount and fix the above heat sink on the CPU or chip, however, a chemical change tends to occur in the adhesive used in the adhering manner on the junction surface, which causes many uncertainties for the fastness of the adhering, the reliability of a long time adhering is low, and the stability of the adhesive for adhering can not be ensured directly, so that all of the above problems are the troubles and defects caused by the conventional heat sink retaining devices.
Therefore, in the conventional heat sink retaining device, if an elastic component is adopted to mount and fix the heat sink on the surface of the CPU or the chip, it has the disadvantage of damaging the heat sink and the stability and being inconvenient in assembling and disassembling, or if the adhering manner is adopted, it has the problems concerning the reliability and fastness. Therefore, how to design a new heat sink retaining device capable of improving the convenience in assembling and disassembling and increasing the reliability and fastness of the combination thereof is the objective of the present invention.